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  2. Primary production - Wikipedia

    en.wikipedia.org/wiki/Primary_production

    Gross primary production (GPP) is the amount of chemical energy, typically expressed as carbon biomass, that primary producers create in a given length of time.Some fraction of this fixed energy is used by primary producers for cellular respiration and maintenance of existing tissues (i.e., "growth respiration" and "maintenance respiration").

  3. Food system - Wikipedia

    en.wikipedia.org/wiki/Food_system

    The term food system describes the interconnected systems and processes that influence nutrition, food, health, community development, and agriculture.A food system includes all processes and infrastructure involved in feeding a population: growing, harvesting, processing, packaging, transporting, marketing, consumption, distribution, and disposal of food and food-related items.

  4. Food web - Wikipedia

    en.wikipedia.org/wiki/Food_web

    A food web is the natural interconnection of food chains and a graphical representation of what-eats-what in an ecological community. Ecologists can broadly define all life forms as either autotrophs or heterotrophs, based on their trophic levels, the position that they occupy in the food web.

  5. Organic matter - Wikipedia

    en.wikipedia.org/wiki/Organic_matter

    Organic matter. Organic matter, organic material, or natural organic matter refers to the large source of carbon-based compounds found within natural and engineered, terrestrial, and aquatic environments. It is matter composed of organic compounds that have come from the feces and remains of organisms such as plants and animals. [1]

  6. Productivity (ecology) - Wikipedia

    en.wikipedia.org/wiki/Productivity_(ecology)

    In ecology, the term productivity refers to the rate of generation of biomass in an ecosystem, usually expressed in units of mass per volume (unit surface) per unit of time, such as grams per square metre per day (g m −2 d −1). The unit of mass can relate to dry matter or to the mass of generated carbon. The productivity of autotrophs, such ...

  7. Production (economics) - Wikipedia

    en.wikipedia.org/wiki/Production_(economics)

    Production is the process of combining various inputs, both material (such as metal, wood, glass, or plastics) and immaterial (such as plans, or knowledge) in order to create output. Ideally this output will be a good or service which has value and contributes to the utility of individuals. [1] The area of economics that focuses on production ...

  8. Raw material - Wikipedia

    en.wikipedia.org/wiki/Raw_material

    A raw material, also known as a feedstock, unprocessed material, or primary commodity, is a basic material that is used to produce goods, finished goods, energy, or intermediate materials that are feedstock for future finished products. As feedstock, the term connotes these materials are bottleneck assets and are required to produce other products.

  9. Biomass (energy) - Wikipedia

    en.wikipedia.org/wiki/Biomass_(energy)

    Biomass (in the context of energy generation) is matter from recently living (but now dead) organisms which is used for bioenergy production. There are variations in how such biomass for energy is defined, e.g. only from plants, [8] or from plants and algae, [9] or from plants and animals. [10] The vast majority of biomass used for bioenergy ...